Davy JonesOfficial Cause of DeathHeart Attack

3/1/2012 10:40 AM PST

Davy Jones Cause of Death -- Heart Attack

Davy Jones died from a heart attack ... this according to the Martin County Medical Examiner.

TMZ has learned ... an autopsy was performed at 10:30 AM EST, and doctors determined Jones died from an abnormal heart rhythm caused by coronary artery atherosclerosis -- in other words, a severe heart attack.

The M.E. still has toxicology results pending, but it was obvious from the autopsy that the heart attack killed the lead singer of the Monkees.